
// let result = Object.is(-0,+0);
// console.log(-0 === +0);
// let result = Object.is(NaN,NaN);
// console.log(NaN === NaN);
// console.log(result);

// Object.assign() 复制(深复制，改变原值)、合并对象
let obj1 = {};
let obj2 = { name:'张三', age: 12 };
let obj3 = { name:'李四', gender: '男'};
Object.assign(obj1,obj2,obj3);
console.log(obj1);